How much alcohol during pregnancy is safe?

Is it ok to have the occasional glass of alcohol when you're pregnant?
Is it ok to have the occasional glass of alcohol when you're pregnant?

South Africa has one of the highest rates of Foetal Alcohol Syndrome (FAS) in the world – with a prevalence as high as 12.2% in some areas. 

Yet women often ask the question, “Is the occasional drink during pregnancy okay?”

A pregnant scientist, Yella Hewings-Martin, investigated.

She came across a study led by Loubaba Mamluk, a senior research associate in epidemiology at the University Hospital Bristol in the UK, that looked into whether it’s safe for a pregnant woman to drink one glass of alcohol per day.  

"The distinction between light drinking and abstinence is indeed the point of most tension and confusion for health professionals and pregnant women, and public health guidance varies worldwide," Mamluk told Hewings-Martin.

The team discovered there was an 8% increase in the risk of having a small baby and a 10% increase in the risk of preterm delivery in women who had about two alcoholic drinks per week.

Is it safe to consume alcohol while pregnant?

Unfortunately it is unlikely that researchers will be able to ascertain conclusively whether it is safe for pregnant women to drink alcohol – in moderation or not.

"This type of research is extremely difficult to perform. It is unethical to attempt to have a group of women intentionally drink, so researchers have limited approaches to study alcohol effects," Professor David Garry, director of maternal foetal medicine at Stony Brook Medicine in New York, told Hewings-Martin.

Alcohol causes damage to cells

It is clear that excessive alcohol consumption is bad for your health. But what effect does it have on the developing foetus?

During her early days a PhD student, Hewings-Martin remembers a routine experiment.

She writes, “I sterilised small glass slides – which I later planned to add cells to – so I could look at them under the microscope.”

She soaked the slides in a 70%-alcohol solution for 15 minutes. “I promptly removed the liquid or so I had thought. Unbeknownst to me, a small amount was left in the petri dish.”

Hewings-Martin says she then made a critical mistake – she added the cells straight away, exposing them to the leftover alcohol. The next day she discovered the cells had died.

“Similar to the way in which the cells in my experiment were bathed in alcohol, in a pregnant mother, alcohol can readily cross the placenta from the blood to the growing baby.”

The developing foetus is unable to break down alcohol as quickly as adults.

“This means that while we may have cleared the alcohol from our system, the baby remains exposed to it for much longer. Longer exposure means more time for alcohol to wreak havoc and kill cells.”alcohol, quote, health24

FAS is preventable

According to a previous Health24 article, babies with FAS are characterised by growth retardation, facial and neural abnormalities as well as malformations of other organ systems. And this condition is 100% preventable.

Professor Garry's advice?

"Avoiding alcohol can be considered one of the most healthy changes for a pregnant woman. No woman desires to harm their child. Using family and friends for support and positive reinforcement can help to reduce stress and avoid the harms of an alcohol-exposed pregnancy."

Image credit: iStock

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